What is self-induced vomiting or laxative abuse used to compensate for excessive food ingestion?

A sample of n = 100 people is classified into four categories. If the results are evaluated with a chi-square test for goodness of fit, what is the df value for the chi-square statistic?

A) ?3 B) ?4 C) ?99 D) ?100

According to the textbook, the main contributor to the increased rate of automobile accidents among teenagers is

A. texting while driving. B. driving under the influence. C. driving with other teenagers in the car. D. talking on the phone, especially having an emotional conversation.